IMRT

Combine Gamma analysis and clinical judgment

120

γ , parametri: soglia 10 cGy δ r 3mm, δ d 3% punti > soglia: 607 γ medio = 0.44+- 0.4(1 dev.st.) γ <1: 554=> 91.3% 1 < γ <= 1.5: 32=> 5.3% γ > 1.5: 21=> 3.5% ∆ d (<10 cGy) = 2 cGy

γ <= 1 γ <= 1.5 γ > 1.5

150

G

100

100

1

80

50

2

Dx

Sx

0

60

-50

40

3

-100

20

-150

1

2

T

3

0

0

0.5

1

1.5

2

2.5

3

-100 -50

0

50

100

γ ≤ 1: 91.3%, not great but not terrible either But many points where γ>1 are in the cord region. If there is overdosage, it may be clinically relevant

L Marrazzo - Florence